Producing diolefins.



UNITED STATES PATENT OFFICE.

FRANZ WEBEII, 01' MANNHEIM, GERMANY, ASSIGNOR TO BADISGHE ANILIN & SODA FABRIK, OI! LU'DWIGSHAFEN-ON-THE-RHINE, GERMANY, A. CORPORATION.

Specification of Letters Patent.

PatentedMay 14, 1912.

1,026,419. No Drawing. Application filed January 30, 1912. Serial No. 674,418.

To all whom it may concern:

Be it known that I, FRANZ WEBEL, sub get of the King of Bavaria, residing at annheim, Germany, have invented new and useful Improvements in Producing 'Diolefins, of which the following is a specification.

In the Journal fair Praktz'cobe Ohemz'e (2), vol. 55, page 5, Ipatiefi' has described the production of a particular diolefin, viz. of isoprene,by heating dibrom-iso entane with alcoholic potash. I have foun however that I can obtain much better yields of diolefins b heatinga monohalogen al 1- one with a so 'd compound which 1s capa 1e of splitting ofl halogen hydrid. The said solid com ound ma efi'ect the splitting oil? of the ha ogen hy rid catalytically or by combining with the halogen hydrid. As instances of compounds which can be employedfor thussplitting ofi halogen hydrid, I mention barium chlorid, nickel chlorid,

lead chlorid, alumina and caustic lime. The reaction is preferably carried out by passing a monohalogen alkylene in the state of vapor through a tube or the like containing the heate solid reagent, and it is also a antageous to carry out the reaction under reduced pressure. The tube containing the barium chlorid or the like, may, for instance, be from about 1 to 3 yards in length.

The process of this invention is of articular advantage for the production 0 diolefins which can be employed inthe production of artificial caoutchouc and similar bodies, for instance, diolefins which contain fqur, five, or six carbon atoms. The following examples will serve to illus trate further the nature of my invention and how it can be carried into practical effeet, but the invention is not confined to I these examples. The parts are by weight.

from 450 to 500 (1., whereupon pure isoprene can be obtained. Now what I claim is 1. The process of producing diolefins by heating a monohalogen a1 lene with a solid compound which is capab e of splitting off halogen hydrid.

2. The process of producing diolefins by heating a monohalogen alkylene under reduced pressure with a solid compound which is capa le of splitting oif halogen hydrid.

3. The process of producing isoprene by heating 3-brom-2-methyl-butene- (2) with caustic lime. I 4. The process of producing isoprene by heating 3-brom-2-methyl-butene- (2) with -caustic lime under reduced pressure.

5. The process of reducing iso rene by passing vaporized 3- br0m-2-methy -butene- (2) at a pressure of from 15 to 20 millimeters over caustic lime at a temperature of from 500 to 520 C.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses. v FRANZ WEBEL. Witnesses:

- A. 0. Tin-MANN, J. Anne. LLOYD. 

